The present invention relates to an optical connector for use in connecting an optical fiber.
In recent years, there is a strong demand for an increase in capacity of optical communication using an optical fiber. Further, in order to reduce the size of an optical communication apparatus, use is made of a PLC (Planar Lightwave Circuit) comprising a silicon or a quartz substrate and a plurality of optical waveguides integrated thereon. In particular, in DWDM (Dense-Wavelength Division Multiplexing), an AWG (Arrayed Waveguide Grating) as one type of the PLC is used so that optical signals transmitted from a plurality of transceivers and different in wavelength from one another can be transmitted by a single optical fiber.
Traditionally, in order to achieve coupling between a number of optical waveguides on the PLC and a number of optical fibers, a component called a fiber array is sometimes used. The fiber array has a number of V grooves. The optical fibers are disposed in the V grooves of the fiber array, respectively, and adhered and fixed thereto. Then, light is transmitted through the optical fibers in the fiber array and the optical waveguides of the PLC and optical power of the light is monitored. When the optical power becomes maximum, the fiber array is adhered and fixed to the PLC.
The above-mentioned technique is called active alignment. The active alignment requires a power monitor and a device for aligning the optical waveguides and the optical fibers in three directions, i.e., back-and-forth, left-and-right, and vertical directions upon coupling the optical waveguides and the optical fibers. Further, a considerably long operating time is required.
Japanese Patent (JP-B) No. 2843338 discloses another example of coupling optical waveguides and optical fibers. The optical waveguides are formed on an optical waveguide substrate. The optical waveguides have end portions located on the optical waveguide substrate in the vicinity of an end face thereof. On opposite sides of the end portions of the optical waveguides, a pair of guide pins are fixed. Each of the guide pins protrudes from the end face of the optical waveguide substrate by about a half of its length.
On the other hand, an optical fiber plug is fixed to end portions of the optical fibers. The optical fiber plug has a pair of receiving holes formed on opposite sides of the end portions of the optical fibers. By inserting the guide pins into the receiving holes, connection between the optical waveguides and the optical fibers is automatically achieved.
With the above-mentioned structure, it is easy to align the optical waveguides and the optical fibers. However, when the guide pins are inserted into the receiving holes, a part of the optical fiber plug which is adjacent to each receiving hole may be damaged by the guide pin. Upon occurrence of such damage, stable alignment is difficult to perform. In order to perform stable alignment, a whole of the optical fiber plug which has been damaged must be replaced by a new optical fiber plug. This requires a relatively high cost.